Dave Jones

13mm per M is min fall so plenty of scope.

I wouldnt have bothered putting down a finished drive before the build starts as it will get destroyed during the build, muck aways, telehandler, digger etc.

450mm chamber can be used upto 1200mm depth. Siteing really doesn't matter put them where you need less bends. It's cheaper to use plastic than have brickie make a chamber with a single benched flow. They come with a 5ton round lid, if you think you will have HGV's going over it for deliveries you can get iron lids.

The GSE kits do work pretty well, they are let down a bit by the rubbish stick on flashing though. nice roof, the slate to metal transition looks very well done.

too cheap. 2-3k now.

who pays the other £10k for the rest ? Farce.

im sure there is an odd exception as you say but its a different colour for a reason. Using the correct stuff saves having to dig out extra paperwork for building control like you have above. Enough hassle when building without making more !!

2300 is still too low for me. What was you build up to FFL ? Could 200mm not have been squeezed out of it ?

because below ground drainage hasn't been manufactured to BS EN 1329 which is required by building regs. Same reason you cant use above ground drainage below ground. Like you say would probably be ok but best to do it properly as the cost isn't that much. https://www.polypipe.com/housing/above-ground-drainage-faqs

there is a much cheaper alternative to the geberit frame that is pretty much identical, the make escapes me but its half the price. It doesnt have the air extraction connection though if thats what you were looking for.

was a little tongue in cheek, they just never are 'that' accurate. ok for modern stuff but where they have transcribed from old paper plans can be literally miles out or not show anything at all when you know its there.

don't be silly. you cant fit architrave above a door with a 2m ceiling. 2300 is the absolute bare minimum for NHBC.

don't see why not, subframe/cavity closer certainly wouldn't stop them.

Building control should pull you up using underground soil fittings inside. Cable tieing water pipes to the soil stack.. hope thats temporary. Any reason you went for metal over timber apart from making life difficult for all the follow on trades ?

for a normal 300mm wall, have a 290mm (to hide the joint) plate welded to the steel to sit the ourside brickwork on. The SE should be speccing this anyway.